JPS629199B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is mainly used in a part of a production line for automobiles, etc., in which parts are assembled sequentially while being continuously conveyed by a conveying device such as an overhead conveyor. By dipping an electrically conductive object such as a body into a water-soluble paint and applying a DC voltage between the object and the paint, the surface of the object is electrophoretically coated. Electrodeposition coating equipment that applies paint, specifically, an electrode plate connected to one electrode of a DC power source is immersed in water-soluble paint, or an electrodeposition device connected to one electrode of a DC power source. a tank, a conveyance device that immerses and moves the object to be coated through the electrodeposition tank while being connected to the other electrode of the DC power source, and a transfer device that is connected to the other electrode of the DC power supply and moves the object to be coated through the electrodeposition tank; The present invention relates to an electrodeposition coating equipment that is equipped with an auxiliary electrode that can be inserted into the interior space of an object being coated while it is being moved through the interior.

In this type of electro-deposition coating equipment, from the perspective of automating the production line, there was a strong demand for complete automation in the electro-deposition coating process. As a practical matter, automation has been difficult in the case of products with

The reason for this is that when a workpiece with an internal space is immersed in electrodeposition coating, the electric field in the internal space is weak and it is difficult to coat the inside surface compared to the outside surface. It is difficult to achieve uniform and good electrodeposition coating over the entire area, and as a countermeasure, generally, as shown in Fig. 5A, in order to strengthen the electric field within the internal space 7', the electrodes connected to the paint side are placed on the same side. This is because it is necessary to insert and set the auxiliary electrode 8' connected to the electrode in the internal space 7' to perform the work. Specifically, since the auxiliary electrode 8' must be connected to an electrode opposite to the object to be coated 5', an auxiliary conveyor C that moves the auxiliary electrode 8' at the same speed as the object to be coated 5' is required. ' and a busper connected to the electrode on the opposite side from the object to be coated 5'.
B', and it is necessary to electrically connect the auxiliary electrode 8' with the cable 11' from the bus bar B' so that the auxiliary electrode 8' can move together with the object to be coated. In this case, as shown in FIG. Then, the auxiliary electrode 8', which moves along with the object 5' inside the electrodeposition tank 4' and comes out of the electrodeposition tank 4' sequentially, is removed from the busper B' and transported from the electrodeposition tank 4'. Replace the auxiliary electrode 8' with the upper busper B' part, and insert the auxiliary electrode 8' into the internal space 7' of the object 5' without contacting the object 5' so that it moves together with the object 5'. It is necessary to perform relatively complicated operations such as replacing the auxiliary electrode 8' and inserting and fixing it into the internal space 7'.
In addition, as the speed of conveying the workpiece 5' changes due to speed-up of the production line, the timing of the manual insertion and fixing work is shifted, making it difficult to carry out the work. It was necessary to install large-scale equipment such as a conveyor C' and a busper B' as a current collecting brush, which required maintenance due to wear and tear.

In view of these circumstances, the present invention has been developed to automatically perform uniform and good electrodeposition coating over the entire inner and outer surfaces of objects having internal spaces using auxiliary electrodes, while using relatively simple equipment. Another object of the present invention is to provide an electrodeposition coating equipment that can easily cope with speed-up or slow-down of a production line.

The characteristic configuration of the present invention, which has been made to achieve the above object, is that, in the above-mentioned electrodeposition coating equipment, the auxiliary electrodes are arranged at appropriate intervals in the moving direction of the object to be coated along the side of the moving path of the object in the electrodeposition bath. A plurality of auxiliary electrodes are arranged in a row so as to be freely retractable with a distance between the auxiliary electrodes.
The main feature is that it is equipped with a control device that is inserted into the internal space of the object to be coated.

The effects of the present invention having such a characteristic configuration are as follows.

In other words, a plurality of auxiliary electrodes are arranged in a row in the direction of movement of the object to be coated along the moving path of the object. By automatically inserting and operating the auxiliary electrode into the internal space, manual operations such as replacing the auxiliary electrode and inserting and fixing it into the internal space are omitted, and the auxiliary electrode can be inserted automatically and continuously.
Uniform and good electrodeposition coating can be performed over the entire inner and outer surfaces using the auxiliary electrodes, and the auxiliary electrodes are not moved together with the object to be coated, but are placed in multiple pieces along the moving path. Because it is installed in a fixed position and is inserted into and withdrawn from the internal space in sequence, it is not susceptible to changes in the conveyance speed of the objects to be coated or changes in the distance between the objects to be coated due to increased production line speed, etc. Therefore, it can be dealt with simply by adjusting the timing of insertion into and exit from the internal space.
This has resulted in the effect of easily responding to speed-up or slow-down of the production line. Furthermore, compared to conventional systems, there is no need to provide large-scale equipment that requires maintenance, such as auxiliary conveyors and buspers, and the equipment can be simplified.

Next, embodiments of the configuration of the present invention will be described based on the drawings.

As shown in FIGS. 1A and 1B, parts of an automobile production line are continuously conveyed by an overhead conveyor 13, which is an example of a conveyance device 6, and are assembled one by one at an assembly station S. The object 5 to be coated, such as the body of a car, which is being transported is immersed in a water-soluble paint.
By applying a DC voltage between the object to be coated 5 and the paint 14, the electrodeposition coating equipment that electrophoretically applies the paint to the surface of the object to be coated 5 is configured. The positive electrode 1a of the power source 1 is connected to a portion corresponding to the upper part of the coating tank 4, and the object 5 to be coated is dipped into the paint 3 via a hanger 15 for suspending and supporting the object 5 from the conveyor 13. The electrodeposition tank 4 is configured to supply a positive current to the object to be coated 5 during conveyance and movement, and the electrodeposition tank 4 is constructed of a conductor, and the negative electrode 1b of the power source 1 is connected to the electrodeposition tank 4. However, it is constructed so that a DC voltage is applied between the object to be coated 5 and the paint 3. Furthermore, the bottom of the electrodeposition tank 4 is provided with a plurality of blow-off ports h for evenly stirring the paint. In addition, in order to prevent the weakening of the electric field of the paint in the internal space 7 of the object 5, the object to be coated is connected to the electrode 1a on the same side as the electrodeposition tank 4 and is moving through the electrodeposition tank 4. Auxiliary electrode 8 that can be inserted into the internal space 7 of 5
A plurality of auxiliary electrodes 8 are arranged in a row along the movement path of the object to be coated 5 at appropriate intervals in the direction of movement thereof, and can move in and out. Accordingly, a control device 9 is provided that sequentially inserts into the internal space 7 based on a preset time schedule.

Next, to construct the auxiliary electrode 8, as shown in FIG. 1B and FIG.
Cylinder 10 that moves 6 in and out using pneumatic or hydraulic pressure
A cable 11 for feeding power to the electrode 14 is wound around a reel 17 that is elastically biased in the direction of winding rotation, and its tip is connected to the electrode, and the cable 11 is connected to the electrode in response to the extension and withdrawal of the pipe 16. The cable 11 is configured to be pulled out without being cut, and the electrode 14 is positioned so that it remains immersed under the paint liquid even when the cylinder 10 is shortened.

Further, the cylinder 10 is normally elongated, and the entrance 7 to the internal space 7 of the object to be coated 5 is closed so as not to contact the object to be coated 5 when the object to be coated 5 passes through.
a, 7b, the auxiliary electrode 8 is configured to move in and out based on a preset time schedule program, and furthermore, in the event that the auxiliary electrode 8
A cylinder intermediate stop detector 18 is provided to detect when the cylinder comes into contact with the workpiece and cannot be extended, and the auxiliary electrode 8 is configured to be swingable in the direction of transport of the object 5 to be coated. A swing detection device 12 for detecting motion is provided, and in an emergency situation where the auxiliary electrode 8 comes into contact with the object 5 to be coated, the conveyor 13 is stopped or the power source 1 is turned off.

Next, in order to operate the auxiliary electrode 8, as shown in FIG. Object detectors 19 for detecting passage of objects to be coated are arranged at intervals l, and are operated based on the program shown in FIG. Configure. In addition, the time schedule program in that case is shown in B. Furthermore, if the program shown in C for determining whether preparations for activating the auxiliary electrode 8 are complete is incorporated as a subroutine in the part marked with ○C in the program shown in A, control without malfunction can be achieved. In addition, the program shown in (d) is used to detect power outages and other emergency situations and operate the equipment safely.

In this way, in order to move the auxiliary electrode 8 in and out according to a preset time schedule without bringing the auxiliary electrode 8 into contact with the object 5 to be coated, the auxiliary electrode 8 The paint on the contact area of the object to be coated 5 will not peel off compared to the electrode that moves in and out, and since the auxiliary electrode 8 is always located within the paint during the movement in and out, it will not be exposed to air. Therefore, the paint does not solidify and adhere to the auxiliary electrode 8 due to drying.

Furthermore, a link mechanism may be incorporated to move the auxiliary electrode 8 backward in the conveying direction of the object 5, and the power source 1 may be any type other than alternating current. A divided waveform current as shown in FIG. 4 may also be used.

Furthermore, depending on the type of paint, the polarity of the electrodes may be reversed from that described above. Also, as mentioned above,
Instead of immersing the electrode plate 2 in the paint 3, a method may be used in which the object 5 to be coated is insulated.

[Brief explanation of the drawing]

The drawings show an embodiment of the electrodeposition coating equipment according to the present invention, and FIG. 1A is an overall schematic side view, FIG. 1B is a schematic sectional view of the main part, FIG. 2 is an enlarged view of the main part, and FIG. ，
B, C, and D are flowcharts of the control program; FIG. 4 is a schematic sectional view showing another embodiment; FIG. 5 A and B are conventional examples; A is a schematic sectional view; B is an explanatory diagram. . 1... Power supply, 1a, 1b... Electrode, 2... Electrode plate, 3... Paint, 4... Electrodeposition bath, 5... To be coated,
6...Transport device, 7...Inner space, 8...Auxiliary electrode, 9...Control device, 10...Cylinder, 11...
...cable, 12...detection device.

Claims (1)

[Claims] 1. Pole plate 2 connected to one electrode 1a of power source 1
The object to be coated 5 is immersed in the water-soluble paint 3, or the electrodeposition bath 4 is connected to one electrode 1a of the power source 1, and the other electrode 1b of the power source 1 is connected to the electrodeposition bath 4. A conveying device 6 that immerses and moves through the electrodeposition tank 4, and an internal space 7 of the object 5 to be coated, which has the same polarity as the electrode plate 2 or the electrodeposition tank 4 and is being moved through the electrodeposition tank 4. In the electrodeposition coating equipment equipped with insertable auxiliary electrodes 8, the auxiliary electrodes 8 are inserted at appropriate intervals along the movement path of the object to be coated 5 in the electrodeposition tank 4 in the direction of movement thereof. A plurality of auxiliary electrodes 8 are arranged in a row in a freely retractable state, and as the object to be coated 5 moves, the auxiliary electrodes at the position where the object to be coated 5 passes, Electrodeposition coating equipment characterized in that it is equipped with a control device 9 that is inserted into the internal space 7 of the object 5 to be coated. 2 The plurality of auxiliary electrodes 8... are connected to the object to be coated 5
Electrodeposition according to claim 1, which is configured to be sequentially inserted into the internal space 7 of the object to be coated 5 based on a preset time schedule as the electrodeposition moves. Painting equipment. 3. The electrodeposition coating equipment according to claim 1, wherein the object to be coated 5 is configured to receive power from a conveyance device 6 side connected to a power source 1. 4. Electrodeposition coating equipment according to claim 1, wherein the auxiliary electrode 8 is provided with a cylinder 10 for moving the object to be coated 5 into and out of the content space 7 side, and a cable 11 for power supply. . 5 The auxiliary electrode 8 is swingable in a direction in which the auxiliary electrode 8 moves together with the object 5 in contact with the object 5 to be coated as the object 5 moves when the object 5 is inserted into the content space 7. The electrodeposition coating equipment according to claim 1, further comprising a detection device 12 for detecting the swinging state.